A2M and glaucoma: The observed upregulation of α2M was previously reported after its quantification by WB in the aqueous humor of 12 patients with POAG, PEXG, and NVG and 9 controls, finding a 3.5-fold increase in glaucoma, probably exerting a neurotoxic effect by inhibiting the neuroprotective activity of nerve growth factor via TrkA receptors, and proposed as a potential biomarker or therapeutic target [99].